38 



AGRICULTURE HANDBOOK 134, U.S. DEPT. OF AGRICULTURE 



Funotiun 



The evaporator house, or sugar house as it is 

 often called, like the evaporator, has developed 

 without engineering design. In the early days 

 of the iron kettle, little thought was given to 

 any form of shelter. At first only a lean-to type 

 of shed was used to protect both the sirup- 

 maker and the boiling sap Ifrom inclement 

 weather, which so often occurs during the sirup 

 season. The shed introduced a new problem — 

 how to get rid of the steam from the boiling sap. 

 This problem was solved by completely enclos- 

 ing the evaporator and installing ventilators at 

 the top. These crude shelters were the forerun- 

 ners of today's evaporator houses. 



Since the evaporator house is used only from 

 4 to 6 weeks each year, its cost must be kept 

 low; otherwise, the interest on the capital in- 

 vestment is out of proportion to its use. The site 

 should permit use of ramps for filling the stor- 

 age tank by gravity (figs. 70 and 71). The house 

 should be constructed so that it not only per- 

 mits sanitary handling of sap and sirup but also 

 provides a place to process and package the 

 sirup, to make confections, and to sell maple 

 products. 



Requirements 



The evaporator house need not be elaborate. 

 It should be large enough to allow plenty of free 



Ife-^-'* 



Figure 68. — Evaporator house located in center of sugar 

 grove. Without a covered evaporator, steam completely 

 fills the evaporator house. This is unfavorable for sani- 

 tary conditions. 



PN-4765 



Figure 69. — The trend is to locate the evaporator house 

 near the other farm building-s and on an improved road. 



space (at least 4 feet) on all sides of the evapo- 

 rator, and it should be set on a foundation that 

 extends below the frostline. The house should 

 be tightly constructed and should have provi- 

 sions for venting the steam. If open hoods are 

 used, there should be intakes to supply air for 

 the fire and to replace air that is exhausted 

 with the steain. Provision should also be made 

 for easy access to the fuel supply and sap 

 storage tanks. 



I)esig;n 



Chart 4 shows a suggested plan for an evapo- 

 rator house with a wing in which the sirup can 

 be processed and maple products can be made. 

 The house itself is designed to contain only the 

 evaporator and a workbench along one wall. 

 The width (16 feet) allows an aisle space of 5 

 feet on each side of an evaporator 6 feet wide 

 to provide easy access to all parts of the evapo- 

 rator. 



.Strain Nontilalion 



In concentrating sap to sirup, vast quantities 

 of steam are produced. Without proper means 



